Endothelin Mechanism of Action
The synthesis of endothelin (ET) in vascular endothelial cells is complex, beginning with preproendothelin, a large precursor molecule. Preproendothelin is processed by furin-like proteases into biologically inactive big endothelins,1 and finally converted by ET-converting enzyme (ECE) to fully active ET.1
Once released from the endothelium, ET exerts its effects through binding to two receptors, ETA and ETB. The consequences of binding differ according to the cell type on which the receptors are found.1,2
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Davie N, Haleen SJ, Upton PD, et al. ET(A) and ET(B) receptors modulate the proliferation of human pulmonary artery smooth muscle cells. Am J Respir Crit Care Med. 2002;165:398–405.
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Muller DN, Mervaala EM, Schmidt F, et al. Effect of bosentan on NF-kappaB, inflammation, and tissue factor in angiotensin II-induced end-organ damage. Hypertension. 2000;36:282–290.
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Katwa LC, Guarda E, Weber KT. Endothelin receptors in cultured adult rat cardiac fibroblasts. Cardiovasc Res. 1993:27:2125–2129.